As the above-mentioned motion guide device, there is known a motion guide device described in Patent Literature 1. The motion guide device described in Patent Literature 1 includes a track rail having a ball rolling surface formed along its longitudinal direction, and a moving block that is assembled to the track rail through intermediation of balls that roll on the ball rolling surface and includes an endless circulation path for the balls. The moving block includes a block main body and a pair of end plates. The block main body has a load ball rolling surface that is opposed to the ball rolling surface of the track rail to form a load ball path for the balls, and a ball return hole for circulating the balls. The pair of end plates has a direction changing path connecting the load ball path and the ball return hole to each other and is fixed to both front and rear end surfaces of the block main body. The balls are circulated through the endless circulation path for the balls, which is provided in the moving block, and thus the moving block can continuously move along the longitudinal direction of the track rail.
In the related-art motion guide device constructed as described above, a scooping portion is provided to the end plate, to thereby scoop the balls having rolled on the ball rolling surface formed in the track rail to guide the balls into the direction changing path formed in the end plate. In such a system of guiding the balls, the scooping portion is required to be arranged at a substantially wedge-shaped space that is formed between a ball spherical surface and the ball rolling surface formed in the track rail, and the scooping portion is thus inevitably configured to have a substantially wedge shape, that is, a taper shape in cross section, which is gradually sloped from the load ball path side to the direction changing path side.
In the related art, there has been a problem in that the tapered scooping portion is damaged due to collision of balls having rolled through the load ball path. That is, the leading end of the scooping portion has a taper shape, and hence the contact area with the ball is small. Accordingly, the contact pressure with respect to the leading end of the scooping portion increases. As a result, there arises a problem in that the leading end of the scooping portion is damaged due to the collision of balls. In the motion guide device according to Patent Literature 1, in order to solve this problem, from the viewpoint of reducing the contact pressure with respect to the scooping portion, the leading end of the scooping portion is formed into a planar shape, and thus the contact area with the ball is increased.